Cognitive Benefits With Continued Donepezil in Alzheimer's

For moderate or severe disease, benefits seen with continued treatment, alone or with memantine

WEDNESDAY, March 7 (HealthDay News) -- For patients with moderate-to-severe Alzheimer's disease, continuation of treatment with donepezil is linked to significant cognitive benefits, according to a study published in the March 8 issue of the New England Journal of Medicine.

Robert Howard, M.D., from King's College London, and colleagues investigated the continued treatment benefits of donepezil following progression to moderate-to-severe Alzheimer's disease. A total of 295 patients with moderate or severe Alzheimer's disease, who had been treated with donepezil for at least three months, were randomly assigned to continue donepezil, discontinue donepezil, discontinue donepezil and start memantine, or continue donepezil and start memantine. Treatment was given for 52 weeks.

The researchers found that, compared with patients assigned to discontinue donepezil, those who continued donepezil had a Standardized Mini-Mental State Examination (SMMSE) score that was an average of 1.9 points higher, and a Bristol Activities of Daily Living Scale (BADLS) score that was 3.0 points lower (reflecting less impairment). Patients who received memantine, compared with memantine placebo, scored 1.2 points higher on the SMMSE and 1.5 points lower on the BADLS. There was no significant difference between donepezil and memantine efficacy in the presence or absence of the other agent. In addition, there were no significant benefits for the combination versus donepezil alone.

"In patients with moderate or severe Alzheimer's disease, continued treatment with donepezil was associated with cognitive benefits that exceeded the minimum clinically important difference and with significant functional benefits over the course of 12 months," the authors write.

Several study authors and the author of the editorial disclosed financial ties to pharmaceutical companies, including Eisai and Pfizer, which manufacture donepezil.